This invention relates to the construction of a motor driven tool and, more particularly, to a construction which provides ease of assembly and added stability and rigidity for the resulting assembly.
Motor driven tools are typically constructed with a two-part clamshell type housing wherein the motor fits within recesses molded as part of the interior of the housing, the attachment together of the two parts of the housing acting to secure the motor therein. This form of construction can present a number of disadvantages, among which is a relatively loose containment of the motor in the housing. Such loose containment leads to a certain amount of instability for the overall tool.
It is therefore a primary object of this invention to provide a tool construction which results in enhanced stability and rigidity of the tool.
Another object is provision of a motor construction wherein the armature and stator are accurately located and accurately positioned relative to a support member.
Another object is provision of a motor support which permits preassembly of the internal components of the machine, prior to final assembly of the motor assembly to the motor housing.
The foregoing and additional objects are attained in accordance with the principles of this invention by providing a power tool comprising a two-part bucket-shaped housing, a motor preassembly connected to the housing, and means for positioning the motor assembly in coaxial relationship to each part of the housing. For the purposes of convenience, the power tool will be referred to as a hand-held orbital polisher. The motor preassembly comprises a motor support peripherally connected to the housing, an armature fixedly connected to the motor support and including an axial shaft arranged vertically and having its opposite respective ends supported for rotation in the motor support and the housing, a stator including a pair of permanent magnets, and means for positioning and retaining the stator in coaxial relation to the armature.
In accordance with a particular aspect of this invention, the housing is integrally formed to include upper and lower housing parts for enclosing the motor assembly, and the motor support is connected to a horizontal housing flange and extends transversely to the motor axis. The motor support positions, locates and aligns the motor assembly, a circuit board, a switch, and electrical wiring for assembly into the housing.
Advantageously, is the simplified assembly of the internal components of the polisher on a single unitary support. The assembly of the internal components is simple because the assembly is conducted external to the motor housing.
Further objects, advantages and features of the present invention will become more fully apparent from the detailed consideration of the arrangement and construction of the constituent parts as set forth in following description taken together with the accompanying drawings.